Due to budgetary constraints imposed during this reporting period it has not been possible to acquire the necessary hardware to interface the microprobe to out PDP 11-60 computer as projected in the last report. Consequently the emphasis of our work shifted to casting into computer programs those algorithms required to convert raw x-ray intensity data into chemical concentrations. These programs include a procedure to unravel spectral overlap, a Monte Carlo procedure to examine the production of x-rays from irregular specimens such as liquid microdroplets and a procedure to perform matrix corrections with a strong emphasis on biological applications. The programs are required to obtain quantitative chemical information from biological samples and are not generally available. The program to correct for the effects of spectral overlap has been completed and reported on. The other two programs are in advanced stage.